特应性皮炎患者尘螨特应性斑贴试验结果分析

目的 分析尘螨变应原不同蛋白浓度的特应性斑贴试验结果,并对诊断价值进行评价.方法 85例特应性皮炎患者,以两个厂家提供的变应原原液进行尘螨变应原的特应性斑贴试验(APT),同时以尘螨变应原的皮肤点刺试验(SPT)及血清特异性IgE测定(SIgE)作为对照,比较APT、SPT、SIgE测定的灵敏度、特异度及阳性预测值,并比较5组不同浓度变应原(3 000、5 000、7 000、10 000、12 000 pnu/g)APT结果,及两个厂家提供的变应原原液间的差异.结果 以SIgE为金标准.1组:APT、SPT检测尘螨的灵敏度分别为79.41％、73.53％;特异度分别为76.12％、80.95％;阳性预测值分别为64.29％、67.57％.2组:APT、SPT检测尘螨的灵敏度分别为81.53％、76.02％;特异度分别为77.78％、79.85％;阳性预测值分别为65.09％、66.07％.以SPT为金标准.1组:APT、SIgE检测尘螨的灵敏度分别为78.38％、67.57％;特异度分别为77.42％、84.21％;阳性预测值分别为67.44％、73.53％.2组:APT、SIgE检测尘螨的灵敏度分别为79.25％、61.07％;特异度分别为80.63％、82.54％;阳性预测值分别为69.55％、77.21％.两组试剂间差异无统计学意义.另外,5种不同浓度的阳性率分别为1组:8.24％、22.35％、29.41％、44.71％、41.18％;2组:3.53％、23.53％、31.76％、34.12％、35.29％,两组试剂间差异无统计学意义(P＞0.05).而两组试剂的各组间APT阳性率差异有统计学意义(P＜0.05),即尘螨变应原浓度的增加会提高APT阳性率,但当浓度达到一定值后阳性率升高不明显.结论 APT诊断尘螨变应原的灵敏度较高,增加变应原蛋白浓度可提高APT阳性率,但达到适宜浓度后阳性率不再升高.

Evaluation of atopy patch test with dust mite allergens for patients with atopic dermatitis

Objective To analyze results of atopy patch test (APT) with dust mite allergens at different concentrations in patients with atopic dermatitis (AD),and to evaluate the diagnostic value of APT.Methods Totally,85 patients with AD were enrolled into this study.All the patients underwent APT with 5 concentrations (3 000,5 000,7 000,10 000 and 12 000 pnu/g) of dust mite allergens,as well as skin prick test (SPT) with dust mite allergens.Dust mite allergens were obtained from two different manufacturers (group 1 and 2).Enzyme-linked immunosorbent assay (ELISA) was performed to detect allergen-specific immunoglobulin E (SIgE) in sera from these patients.The sensitivity,specificity and positive predictive value of APT,SPT and SIgE assay were compared,and the results of APT were compared among different concentrations of allergens and between allergens from different manufacturers.Results When SIgE assay served as the gold standard,the sensitivity,specificity and positive predictive value in the diagnosis of dust mite allergy were 79.41％,76.12％,and 64.29％ respectively for APT,73.53％,80.95％ and 67.57％ respectively for SPT with group 1 dust mite allergens,and 81.53％,77.78％ and 65.09％ respectively for APT,76.02％,79.85％ and 66.07％ respectively for SPT with group 2 allergens.When SPT was regarded as the gold standard,the sensitivity,specificity and positive predictive value in the diagnosis of dust mite allergy were 78.38％,77.42％,67.44％ respectively for APT,67.57％,84.21％,73.53％ respectively for SIgE assay with group 1 dust mite allergens,79.25％,80.63％ and 69.55％ respectively for APT,61.07％,82.54％ and 77.21％ respectively for SIgE assay with group 2 allergens.There were no significant differences in the sensitivity,specificity or positive predictive value of APT or SPT between the two groups of allergens.The positive rate of APT was 8.24％,22.35％,29.41％,44.71％ and 41.18％ respectively with group 1 allergens at 3 000,5 000,7 000,10 000 and 12 000 pnu/g,and 3.53％,23.53％,31.76％,34.12％ and 35.29％ respectively with group 2 allergens.No significant differences were observed in the positive rate of APT between group 1 and 2 allergens at same concentrations (all P ＞ 0.05),but a significant difference was observed in that between different concentrations of group 1 or 2 allergens (both P＜ 0.05).The positive rate of APT increased with the increase of allergen concentrations,but stopped rising when the concentrations of group 1 and 2 allergens reached 7 000 pnu/g and 5 000 pnu/g respectively.Conclusions The sensitivity of APT is relatively high for the diagnosis of dust mite allergy.The positive rate of APT increased with the increase in allergen concentrations,but stopped rising when the concentrations reached a certain level.